Occupant monitoring systems and methods

ABSTRACT

Various implementations include an occupant monitoring system (OMS) for monitoring at least one occupant in a vehicle. The OMS includes a mounting bracket coupled to a rotatable portion of a steering wheel assembly, a housing coupled to the mounting bracket, at least one imaging unit disposed within the housing, and at least one lens disposed adjacent the housing and imaging unit and facing an expected position of at least one vehicle occupant and configured for allowing light to pass through to the imaging unit. The mounting bracket extends upwardly from the steering wheel assembly adjacent a central portion thereof. The housing has a back surface that is disposed adjacent a back cover of the steering wheel assembly. The imaging unit has a field of view inside of the vehicle and is configured to capture an image signal corresponding to an imaging area within the field of view.

TECHNICAL FIELD

This disclosure generally relates to an occupant monitoring system. Morespecifically, this disclosure relates to a vehicle steering assemblyincluding an occupant monitoring system.

BACKGROUND

Various advanced driver assistance systems incorporate visual, acoustic,and/or sensor warnings. Many of these warnings are in response tooutside dangers (e.g., proximity of another object). However, in recenttimes, the number of potential distractions for a driver has increased(e.g., mobile phones, mp3 players, internal displays, etc.). Drivermonitoring systems are becoming more and more popular for inclusion invehicles, such as, to warn when the driver is detected to be in anon-alert state.

SUMMARY

Various implementations include an occupant monitoring system (OMS) formonitoring at least one occupant in a vehicle that has a steering wheelassembly configured to rotate relative to a steering column. The OMSincludes a mounting bracket coupled to the steering wheel assembly, ahousing coupled to the mounting bracket, at least one imaging unitdisposed within the housing, and at least one lens disposed adjacent thehousing and imaging unit. The mounting bracket extends upwardly from thesteering wheel assembly adjacent a central portion thereof. The housinghas a back surface that is disposed adjacent a back cover of thesteering wheel assembly. The imaging unit has a field of view inside ofthe vehicle and is configured to capture an image signal correspondingto an imaging area in the vehicle. The imaging area is within the fieldof view. The lens has a front surface configured for allowing light topass therethrough to the imaging unit. The front surface of the lensfaces an expected position of at least one occupant in the vehicle.

In some implementations, the mounting bracket is separately formed froma frame of the steering wheel assembly and is fastened to the frame. Thefastening mechanism may include any suitable mechanical fastener, suchas screws, clips, etc. or chemical or other fastening means, such asadhesive, welding, etc. In other implementations, the mounting bracketmay be integrally formed with a frame of the steering wheel assembly.

In some implementations, the OMS includes at least one light sourceadjacent the imaging unit. The light source may be disposed on one ormore printed circuit boards disposed within the housing. The printedcircuit boards may be coupled to the mounting bracket and include athermal coupling material between each printed circuit board and themounting bracket. The thermal coupling material, which may include athermal coupling pad or paste, for example, is configured fortransferring heat from the printed circuit board to the mountingbracket. The mounting bracket includes a material configured fortransferring heat away from the printed circuit boards.

For example, in certain implementations, a first light source isdisposed on a left side of the imaging unit and a second light sourcedisposed on a right side of the imaging unit. The front surface of thelens is further configured for allowing light from the first and secondlight sources to pass therethrough out of the housing. And, in someimplementations, each of the first and second light sources may includea set of two or more light emitting diodes. Each set of two or morelight emitting diodes may be disposed on one or more printed circuitboards disposed within the housing, and a thermal coupling material maybe disposed between the printed circuit boards and the housing.

In some implementations, at least one of the printed circuit boardsincludes a processing unit. The processing unit is electrically coupledto the imaging unit and is configured for receiving image signals fromthe processing unit. In certain implementations, the processing unit isconfigured for selecting at least a portion of the image signals asbeing related to one or more occupant information parameters andcommunicating the selected image signals to a second processing unitdisposed outside of the housing. The processing unit may also beconfigured for selecting at least a portion of the image signals asbeing related to one or more occupant information parameters,calculating data related to the selected image signals, andcommunicating the calculated data to a second processing unit disposedoutside of the housing.

According to certain implementations, the OMS includes at least onelight source disposed adjacent the imaging unit and a light blockingmaterial disposed between the imaging unit and the light source. Thelight blocking material extends at least between a distal end of theimaging unit and the OMS lens and is configured for preventing lightfrom the light source from entering the imaging unit prior to the lightexiting the lens of the OMS. For example, in some implementations inwhich the imaging unit is a camera, the camera has a lens disposed at adistal end thereof through which light enters the camera. The lightblocking material includes a compressible ring disposed between thedistal end of the camera lens and the lens of the OMS. In someimplementations, the ring may be an annular ring or other suitable shapeconfigured to fit adjacent the perimeter of the camera lens. In otherimplementations, the light blocking material may extend between theimaging unit or mounting bracket and the OMS lens.

The OMS lens, according to certain implementations, may be configuredfor optically blocking visible light and allowing infrared light to passthrough the lens. For example, the lens may be made of an acrylic-basedmaterial that is opaque to visible light. For example, the lens may bemade from a poly(methyl methacrylate) (PMMA) material (e.g., ACRYLITE).In other implementations, the lens may be formed from any polycarbonatematerial, such as, for example, polycarbonate (e.g., LEXAN),acrylonitrile butadiene styrene polycarbonate (ABS-PC), PC-ABS,acrylic-styrene-acrylonitrile terpolymer polycarbonate (ASA-PC), orother plastics that include polycarbonate as a major alloying element.In addition, the lens may be formed from glass, cellulose acetatebutyrate (CAB) or butyrate, glycol modified polyethylene terephthalate(PET-G), or other polymers, for example. Furthermore, the lens may beblock ultraviolet light and/or may be flat or curved. In addition, thelens may be cut from stock or molded into shape.

The OMS may also include at least one trim piece shaped to fit around atleast a portion of a side or an upper perimeter of the lens, accordingto some implementations. The trim piece is configured for securing atleast a portion of the lens relative to the mounting bracket. Forexample, in one implementation, the trim piece includes an upper portionand right and left side portions that extend from each of the right andleft ends, respectively, of the upper portion. The upper portion isconfigured for engaging an upper perimeter of the lens, the right sideportion is configured for engaging a right side perimeter of the lens,and the left side portion is configured for engaging a left sideperimeter of the lens. The trim piece also includes a first tab and asecond tab. The first and second tabs extend inwardly from the right andleft side portions of the trim, respectively, and each tab defines anopening configured for receiving a screw. The openings are configuredfor aligning with openings defined in the housing and the mountingbracket, and each opening in the tabs, housing, and mounting bracket isconfigured for receiving a screw to secure the housing and trim piece tothe mounting bracket.

In some implementations, the OMS also includes a lens support piececoupled to the mounting bracket adjacent a lower perimeter of the OMSlens. The lens support piece prevents movement of the lower perimeter ofthe OMS lens relative to the mounting bracket. The lens support piecemay define a channel on an upper surface thereof, and the lowerperimeter of the lens is configured for engaging the channel.

In certain implementations, the back surface of the housing extendswithin the same plane as the back cover of the steering wheel assembly.

In addition, in some implementations, the imaging unit is coupled to themounting bracket.

The details of one or more implementations of the invention are setforth in the accompanying drawings and the description below. Otherfeatures, objects, and advantages of the invention will be apparent fromthe description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

The device is explained in even greater detail in the followingdrawings. The drawings are merely exemplary to illustrate the structureof preferred devices and certain features that may be used singularly orin combination with other features. The invention should not be limitedto the examples shown.

FIGS. 1A and 1B are schematic views of exemplary occupant monitoringsystems;

FIGS. 2A-F are schematic views of exemplary imaging units;

FIGS. 3A and 3B are schematic views of exemplary occupant monitoringsystems;

FIGS. 4A-D are schematic views of exemplary occupant monitoring systems;and

FIG. 5 is a schematic view of an exemplary processing unit.

FIG. 6 is a front view of a steering wheel according to oneimplementation.

FIG. 7 is a side cut out view of the clock spring shown in FIG. 4 asviewed along the C-C line.

FIG. 8 is a perspective view of a wire ribbon according to oneimplementation.

FIG. 9 is a side cut out view of a clock spring according to anotherimplementation.

FIG. 10 is a schematic view of various components of the OMS accordingto one implementation.

FIGS. 11A and 11B illustrate a slip ring according to oneimplementation.

FIG. 12 is a perspective view of various components of the OMS,including the lens, assembled together, according to one implementation.

FIG. 13A is a perspective, exploded front view of the OMS shown in FIG.12.

FIG. 13B is a perspective, exploded rear view of the OMS shown in FIG.12.

FIG. 14 is a perspective, assembled front view of the OMS shown in FIG.12 without the lens.

FIG. 15 is a schematic, top view of certain components of the OMS shownin FIG. 12.

FIG. 16 is a spectral transmission curve showing the percent of lighttransmitted at various wavelengths through an ACRYLITE lens, accordingto one implementation.

FIGS. 17A and 17B are front perspective and rear views, respectively, ofa housing according to one implementation.

FIGS. 18A and 18B are front perspective and rear views, respectively, ofa housing according to another implementation.

FIGS. 19A and 19B are front perspective and rear views, respectively, ofa housing according to yet another implementation.

FIG. 20 is a top view of the steering wheel assembly and the housingshown in FIG. 12 coupled thereto, according to one implementation.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Certain exemplary implementations of the invention will now be describedwith reference to the drawings. In general, such implementations relateto an occupant monitoring system (OMS) for monitoring occupants in avehicle via one or more imaging units. For example, in variousimplementations, the OMS includes an imaging unit, such as a camera,that is coupled to a rotating portion of a steering wheel assembly, suchas the central hub portion. The imaging unit has a field of viewdirected toward one or more occupants in the vehicle and is configuredto capture an image signal corresponding to an imaging area in the fieldof view. The imaging area can be configured to encapsulate an expectedposition of the occupant, for example. The OMS also includes one or moreprocessing units in electrical communication with the imaging unit thatreceives and processes the image signal from the imaging unit todetermine an occupant state and, in some implementations, providefeedback (e.g., output) based on the determined occupant state.

FIG. 1A is a schematic view of an exemplary occupant monitoring system(OMS) 100 for monitoring a driver 102 in a vehicle. In thisimplementation, the OMS 100 may be coupled to the vehicle's steeringwheel assembly 104. The OMS 100 and/or the steering wheel assembly 104can be configured to rotate relative to the vehicle's steering column106. The steering wheel assembly 104 can be coupled to the vehicle'ssteering input shaft 107, steering column 106, or any other vehiclecomponent used to translate driver input to control instructions for thevehicle (e.g., including drive by wire technology). For example, asillustrated in FIG. 1A, the steering wheel assembly 104 can be coupledto the vehicle's steering input shaft 107 that is in turn coupled to thevehicle's steering column 106. The steering column 106 can be anon-rotating, component within the vehicle. In some implementations, thesteering column 106 may include a tilt and/or extension mechanism (e.g.,a telescopic mechanism) that allows for the adjustment of the steeringwheel assembly 104 closer to, away from, or at a different anglerelative to the driver. The tilt/extension mechanism may be referred toas “tilt and telescope” or “reach and rake,” for example.

In some implementations, the steering column 106 can receive thesteering shaft 107 that extends along a steering axis and serves totranslate rotational movement of the steering wheel assembly 104 to thewheels of the vehicle. Rotational movement of the steering wheelassembly 104 can be transmitted to the wheels by mechanical and/orelectrical means.

As illustrated in the exemplary system shown in FIG. 1B, the steeringwheel assembly 104 includes a rim 114 and a hub 116. The steering wheelassembly 104 can also include at least one spoke 118 connecting the rim114 to the hub 116. The rim 114 can comprise a single continuous portionor any number of unique sections that the driver can grip to facilitatecontrol of the vehicle. For example, the rim 114 can include an annularring shape with an outer contour that is essentially circular in shape.In alternate implementations, the rim 114 can define any suitable shapeincluding, for example, circular, elliptical, square, rectangular,semi-circular, semi-elliptical, or any other regular or irregular shape.In addition, in some implementations, the rim may include two or moresemi-circular, semi-elliptical, semi-rectangular, or other regular orirregular shaped portions coupled to the hub. For example, in oneimplementation, the rim may include two semi-circular rim sectionscoupled to the hub (e.g., resembling a flight yoke). The hub 116 can bedisposed central to the rim 114. The hub 116 can provide the connectionpoint between the steering wheel assembly 104 and the vehicle's steeringshaft 107/steering column 106.

As illustrated in implementations shown in FIGS. 1A and 1B, the OMS 100is coupled to a central portion 112 of the steering wheel assembly 104.The central portion 112 can include, for example, the spoke 118, the hub116, and/or any other portion of the steering wheel assembly 104centrally located with respect to the rim 114. As used herein “and/or”includes implementations having element A alone, element B alone, orelements A and B taken together. For example, the central portion 112can include the spoke 118 and/or the hub 116 is meant to includeimplementations wherein the central portion 112 includes the spoke 118,the hub 116, or the spoke 118 and the hub 116.

Coupling and integrating the OMS 100 with the central portion 112 of thesteering wheel assembly 104 can allow for increased viewing angles andimproved resolution of the imaging area by an imaging unit 108 of theOMS 100 of the driver 102 and/or other vehicle occupant regardless ofthe rotation of the steering wheel assembly 104. For example, if the OMS100 were mounted to a non-rotating component, such as the steeringcolumn 106, the OMS 100 view of the driver 102 or occupant could beobscured by the spoke(s) 118 when the steering wheel assembly 104 isrotated, or by the rim 114 by being positioned rearwards in relation tothe steering wheel assembly 104. In addition, mounting the OMS 100 to anon-rotating component of the vehicle would increase the distancebetween the imaging unit 108 and the occupants in the vehicle.

In addition, the central portion 112 of the steering wheel assembly 104in a vehicle can also contain an airbag. Generally, the driver knows toposition his/her hands and/or body in certain positions relative to thesteering wheel assembly 104 for safety due to the airbag. Coupling theOMS 100 to the central portion 112 of the steering wheel assembly 104can also take advantage of this conditioned driver positioning andminimizes the likelihood of the driver 102 obscuring the OMS 100.

Furthermore, one or more components of the OMS 100 may be mounted to therim 114 in some implementations. For example, as described more below, alight source for illuminating at least a portion of a field of view ofthe imaging unit 108 may be included in a light bar system disposed onthe rim 114. However, by mounting components of the OMS 100 to thecentral portion 112, the OMS 100 components may be less likely to beobscured by the driver's hands during normal operation of the vehicle.

Furthermore, the three-dimensional position of the steering wheelassembly 104 in a vehicle (e.g., height, angle, tilt, etc.) is usuallyadjustable to accommodate a wide range of drivers and/or other vehicleoccupants (e.g., drivers or occupants of varying heights, weights,proportions, ages, ethnicities, genders, experience, etc.).Incorporation of the OMS 100 into the steering wheel assembly 104 canallow for the OMS 100 to take advantage of this adjustment, andtherefore accommodate a wide range of drivers and driver positions.

As noted above, the OMS 100 includes at least one imaging unit 108configured to capture an image signal corresponding to an imaging area110 in the vehicle. The imaging area 110 may include the field of viewof the imaging unit 108 or a portion thereof. The image signal, forexample, can comprise an optical representation of an instant value ofthe imaging area 110. In some implementations, the imaging area 110 canbe configured to encapsulate an expected position of the driver 102and/or other vehicle occupant. The imaging unit 108 can be configuredfor rotating with the steering wheel assembly 104 of the vehicle. Invarious implementations, the imaging unit 108 can be disposed on anyportion of the central portion 112 of the steering wheel assembly 104.

The imaging unit 108 can include an instrument capable of capturing animage signal corresponding to the imaging area 110. For example, theimaging unit 108 can comprise a spectrometer, a photometer, a camera, ora combination thereof. In some implementations, such as in FIG. 2A, theimaging unit 108 includes a camera 120. The camera 120 can be any typeof camera consistent with the systems and methods described herein. Insome implementations, the camera can have a high resolution, lowresolution, capable of capturing still and/or moving images. In someimplementations, the camera 120 can be any suitable digital camera thatcan capture an image signal corresponding to the imaging area. Suitablecamera platforms are known in the art and commercially available fromcompanies such as Zeiss, Canon, Applied Spectral Imaging, and others,and such platforms are readily adaptable for use in the systems andmethods described herein. In one implementation, the camera 120 mayinclude a fish eye camera. The camera 120 can feature simultaneous orsequential capture of one or more wavelengths using either embeddedoptical filters within the camera 120 or external filters. The camera120 can, in some implementations, comprise a lens (e.g., a wide anglelens, a fisheye lens, etc.), adaptive optics, other evolving optics, ora combination thereof.

In some implementations, the imaging unit 108 may be part of a vehicleoccupant imaging system 109 that is part of the OMS 100. The vehicleoccupant imaging system 109 can also include at least one light source122. The light source 122 can be any type of light source capable ofilluminating at least a portion of the field of view of the imaging unit108 and/or the imaging area 110. The imaging unit 108 can comprise asingle light source 122 or any number of light sources 122. Moreover,different types of light sources 122 may be implemented. In someimplementations, the one or more light sources 122 can illuminate theimaging area 110 with light of different wavelengths (e.g., one lightsource 122 can illuminate with a different wavelength or range ofwavelengths than the other light source(s) 122). Examples of suitablelight sources 122 include artificial light sources such as incandescentlight bulbs, light emitting diodes, and the like. Furthermore, the lightsource can be a continuous light source (e.g., incandescent light bulbs,light emitting diodes, continuous wave lasers, etc.), a pulsed lightsource (e.g., pulsed lasers), or a combination thereof. In addition, inimplementations that include light sources 122 configured forilluminating with different wavelengths, such as, for example, a firstlight source configured for illuminating infrared light and a secondlight source configured for illuminating visible light, the lightsources 122 having different wavelengths may be configured forperforming different functions. For example, the infrared light sourcemay be configured for illuminating at least a portion of the field ofview of the imaging unit 108 and the visible light source may beconfigured for communicating information to the driver or otheroccupants.

In some embodiments, the light source 122 can be any light source thatemits one or more wavelength between 300 and 2500 nm. In someembodiments, the light source 122 emits a broad range of wavelengths,and a filter can be used to select a wavelength of interest. In someembodiments, a range of wavelengths is selected. Any type of filterconsistent with the systems and methods described herein can be used.For example, the filter can be an absorptive filter, a dichroic filter,a monochromatic filter, a longpass filter, a bandpass filter, ashortpass filter, or a combination thereof. In some embodiments, thefilter is an external filter. In some embodiments, the filter isembedded in the light source 122. In some embodiments, the filter isembedded in the vehicle occupant imaging system 109 and/or may includeat least one optical film. In some implementations, the light source 122can emit a wavelength or range of wavelengths of interest. In someimplementations, the light source 122 can emit a range of wavelengths offrom 800 nm to 1000 nm. In some implementations, the light source 122can comprise an infrared light source (e.g., a light source emitting oneor more wavelengths from 750 nm to 1,000,000 nm), such as anear-infrared light source, a mid-infrared light source, a far-infraredlight source, or a combination thereof.

In certain implementations, a processing unit may be configured foradjusting an intensity of the light source 122 based on ambient lightingconditions in the field of view of the imaging unit 108. For example,the intensity of light emitted from the light source 122 may bedetermined by the processing unit based on the image signals receivedfrom by the imaging unit 108, according to one implementation.

In some implementations, the light source 122 can include a light bar124. The light bar 124 can include, for example, a liquid crystaldisplay (LCD), thin-film-transistor display, active-matrix display, asegmented display (e.g., improved black nematic (INB), super twistednematic (STN), etc.), one or more light-emitting diodes (LED), a liquidcrystal display, laser, halogen, fluorescent, an infra-red (IR) LEDilluminator, or any other suitable light emitting element. For example,in some implementations, the light bar 124 may include one or more LEDsthat emit one or more wavelengths in the visible range (e.g., 350 nm to750 nm). In another implementation, the light bar 124 may include one ormore LEDs that emit infrared light. And, in yet another implementation,the light bar 124 may include a first set of LEDs that emit one or morewavelengths in the visible range and a second set of LEDs that emit oneor more wavelengths in the infrared range. For example, in variousimplementations, the light bar 124 includes at least a first section ofLEDs that emit visible light and at least a second section of LEDs thatemit infrared light. The LEDs in the second section may be configuredfor illuminating at least a portion of the field of view of the imagingunit 108, and the LEDs in the first section may be configured forcommunicating information to the driver or other occupant. For example,in one implementation, the LEDs in the first section are configured forilluminating visible light in response to the OMS being in one of anoperational mode or a non-operational mode. In another implementation,the LEDs in the first section may be configured to illuminate duringvehicle operation to provide a warning to the driver or other occupants.And, in yet another implementation, the LEDs in the first section may beconfigured to flash one or more times at vehicle start up to indicatethat the OMS is in an operational mode and then illuminate duringvehicle operation to provide a warning to the driver or other occupants.

In some examples, the vehicle occupant imaging system 109 may use anexternal light source in addition to or instead of light source 122. Asused herein, an external light source includes any light source that isnot part of the OMS 100. For example, the external light source caninclude a natural light source, such as the sun. Other examples ofexternal light sources include ambient light, such as from street lamps,the headlights and/or taillights from other vehicles, electronicdisplays within the vehicle cabin, cabin lights, etc. In some examples,the vehicle occupant imaging system 109 can use an external light source(not shown) that is electrically coupled to the vehicle occupant imagingsystem 109 such that the external light source is configured toilluminate the field of view of the imaging unit 108 and/or the imagingarea 110.

In some implementations, the light source 122 may include the light bar124, another light source, such as those described above, or acombination thereof.

It is to be understood that as used herein, the singular forms “a”,“an,” and “the” include the plural referants unless the context clearlydictates otherwise. Thus, for example, reference to “a camera,” “a lightsource,” or “a light bar” includes combinations of two or more suchcameras, light sources, or light bars, and the like. The componentscomprising the vehicle occupant imaging system 109 can be configured inany way consistent with the systems and methods described herein.

Some exemplary configurations of the vehicle occupant imaging system 109are illustrated in FIG. 2A-2F. In the implementation shown in FIG. 2A,the vehicle occupant imaging system 109 includes a camera 120. Anexternal light source (not shown), such as an artificial light source,the sun or other available ambient light, is used to illuminate thefield of view and/or imaging area of the camera 120.

In the implementation shown in FIG. 2B, the vehicle occupant imagingsystem 109 includes camera 120 and one or more light sources 122disposed proximate and above the camera 120. In the implementation shownin FIG. 2C, the vehicle occupant imaging system 109 includes camera 120and light bar 124 disposed proximate and above the camera 120.

In other implementations, one or more individual light sources 122 orlight bars 124 (or combinations thereof) may be disposed below and/or tothe sides of the camera 120 or adjacent other locations on the steeringwheel assembly 104, vehicle, or vehicle occupant imaging system 109. Forexample, in the implementation shown in FIG. 2D, the vehicle occupantimaging system 109 includes camera 120, individual light source 122disposed proximate and above camera 120, and light bar 124 disposedproximate and below camera 120. As another example, the vehicle occupantimaging system 109 shown in FIG. 2E includes camera 120, two individuallight sources 122 disposed proximate and to the sides of camera 120, andlight bar 124 disposed proximate and above the camera 120. In anotherexample, as illustrated in FIG. 2F, the vehicle occupant imaging system109 may include camera 120, two individual light sources 122 a, 122 b,and two light bars 124 a, 124 b. A first light source 122 a is disposedproximate to a right side of the camera 120, a second light source 122 bis disposed proximate to a left side of the camera 120, a first lightbar 124 a is disposed proximate to a right side of the first lightsource 122 a, and a second light bar 124 b is disposed proximate to aleft side of the second light source 122 b.

Any number of cameras 120, light sources 122, and/or light bar 124combinations or configurations is contemplated.

During normal operation of a vehicle, the central portion 112 of thesteering wheel assembly 104 is readily observable by the driver 102. Inorder for the presence of the OMS 100 to not alter the driver's normaloperation of the vehicle, the OMS 100 may be coupled to the steeringwheel assembly 104 so as to be non-visible or unobtrusive to the driver102. For example, the OMS 100 can be hidden from the driver 102 behind astyle element. Moreover, the position of the vehicle occupant imagingsystem 109 can also be optimized for safety of the driver's eyes.

For example, one or more components of the OMS 100, such as the imagingunit 108 and/or the light source 122, may be disposed within a housing.The housing can be permanently and/or removably coupled to the steeringwheel assembly 104. In addition, the housing may be integrally formedwith or separately formed from and mounted to the steering wheelassembly 104 according to various implementations. For example, in someimplementations, the housing may be integrally formed with a backcover126 of the hub 116, and one or more components of the OMS 100 can bedisposed in the housing formed with the backcover 126. In one suchimplementation, the OMS 100 components disposed in the backcover 126rotate with the steering wheel assembly 104. In other implementations,the housing may be integrally formed with a portion of the hub 116 thatis adjacent to or includes a driver air bag or switch assembly. And, inother implementations, the housing may be separately formed from thesteering wheel assembly 104 and coupled to it using any suitablefastening technique, such as, for example, screws, hooks, clips,adhesive (e.g., glue), soldering, or welding. The housing may be coupleddirectly to the steering wheel assembly 104 or to a mounting bracket,such as mounting bracket 301 described below in relation to FIGS. 12-15,or other structure that is coupled to the steering wheel assembly 104.

FIGS. 3A through 3B illustrate various implementations of the housing ofthe vehicle occupant imaging system 109 coupled to the steering wheelassembly 104. For example, in the implementation shown in FIG. 3A, thehousing for the vehicle occupant imaging system 109 is coupled to anupper portion of the hub 116 of the steering wheel assembly 104.Components of the vehicle occupant imaging system 109 are disposedwithin the housing. FIG. 3B illustrates a side view of the housing forthe vehicle occupant imaging system 109 that is shown in FIG. 3A. Thebackcover 126 to which the housing is coupled is part of the hub 116.

FIG. 4A through 4D illustrate various implementations of components ofthe vehicle occupant imaging system 109 coupled adjacent to the steeringwheel assembly 104. In particular, FIG. 4A provides a front view of thesteering wheel assembly 104 with components of the vehicle occupantimaging system 109 coupled adjacent to the backcover 126. For example,in some implementations, the components may be coupled directly to thesteering wheel assembly and/or the housing noted above in FIGS. 3A and3B. In other implementations, the components may be coupled to at leastone mounting bracket or other intermediate structure(s) that is coupleddirectly to the steering wheel assembly and/or housing FIG. 4B providesan angled front view of the steering wheel assembly 104 with componentsof the vehicle occupant imaging system 109 coupled adjacent to thebackcover 126. FIG. 4C provides a top-down view of the steering wheelassembly 104 with components of the vehicle occupant imaging system 109coupled adjacent to the backcover 126. FIG. 4D provides a close up viewof the section marked “4D” in FIG. 4A showing components of the vehicleoccupant imaging system 109 coupled adjacent to the backcover 126. Inthese or other implementations, other components of the OMS 100, such asone or more processing units, may also be disposed adjacent to thesteering wheel assembly, such as within the housing coupled to thebackcover 126. Alternatively, the other components of the OMS 100 may bedisposed on other portions of the steering wheel assembly 104 or outsideof the steering wheel assembly 104 within the vehicle.

In some implementations, it may be desirable to thermally couple the OMS100 or portions thereof to the backcover 126 and/or other portions ofthe steering wheel assembly 104 to dissipate heat away from the portionsof the OMS 100 and allow for improved heat exchange. For example, thehousing in which components of the vehicle occupant imaging system 109are disposed may be formed of a thermally conductive material andcoupled to the backcover 126 using a thermally conductive “gap pad” orother thermally conductive adhesive or mechanical heat sink, accordingto certain implementations. For example, the housing, backcover 126, andsteering wheel assembly 104 may be constructed of materials having highthermal conductivity, including, for example, magnesium alloy (diecast)(1.575 W/cm·C.°), aluminum alloy (diecast) (2.165 W/cm·C.°), and steel(low carbon) (0.669 W/cm·C.°).

In some implementations, the housing can be coupled to the backcover 126or other portions of the steering wheel assembly 104 using a mountingbracket, such as shown and described below in relation to FIGS. 12through 20, or may be directly coupled to the back cover 126 or otherportions of the steering wheel assembly 104. Heat from the OMS 100components disposed within the housing are conducted from the housing tothe backcover 126 and/or the steering wheel assembly 104 directly or viathe mounting bracket, allowing the back cover 126 and/or steering wheelassembly 104 to act as a heat sink for the OMS 100.

In some implementations, the OMS 100 can further include a steeringangle sensor 128, as shown in FIG. 3B. The steering angle sensor 128 canbe mounted proximate to the steering wheel assembly 104 and can provideactive feedback about the position, angle, rate of rotation, and/ororientation of the steering wheel assembly 104. The steering anglesensor 128 may be disposed between a non-rotating and a rotating elementof the steering wheel assembly 104. For example, as shown in FIG. 3B,the steering angle sensor 128 may be coupled to the steering column 106,which does not rotate. Alternatively (not shown), the steering anglesensor 128 may be coupled to the steering shaft 107, which rotatesrelative to the steering column 106. In another example, which is shownin FIG. 6, the steering angle sensor 128 is disposed in a stator of anautomotive clock spring. Alternatively (not shown), the steering anglesensor 128 may be disposed in a rotor of the automotive clock spring.

The steering angle sensor 128 can be an analog device, a digital device,or a combination thereof. For example, the steering angle sensor 128 caninclude a rotating, slotted disc; an LED light; and a detector. The LEDlight is positioned to transmit light through the slotted disc to thenbe collected by the detector. The detector can output a signal based onwhether or not any light is detected according to the slit position. Byknowing the slit positions and counting the number of times light/nolight are detected, the rotation speed and direction can be determined.The OMS 100 can utilize a dedicated steering angle sensor 128, or theOMS 100 can utilize an existing sensor integrated in the steering wheelassembly 104 and/or other vehicle component.

In various implementations, the OMS 100 is associated with controlcircuitry for controlling its operation. For example, the OMS 100 can beassociated with circuitry for controlling operation of the vehicleoccupant imaging system 109 including, for example, operation of thecamera 120 and/or light source 122. In an exemplary implementation, theOMS 100 may be wired directly to the control circuitry of the steeringwheel assembly 104. For example, the light source 122 can be wiredthrough an inline resistor to a steering wheel assembly power source(not shown).

In some implementations, the OMS 100 includes a processing unit 200. Theprocessing unit 200 can be configured to provide operation instructionsto/from the vehicle and various OMS 100 components. The processing unit200 can be configured to direct operation of the OMS 100. The processingunit 200 can be part of and disposed adjacent the vehicle occupantimaging system 109 and/or disposed on or otherwise associated with theelectronic control unit (ECU) of the vehicle. In a furtherimplementation, the processing unit 200 may be located on or otherwiseassociated with another vehicle system. Where the processing unit 200 isassociated with a system other than the OMS 100, communication lines(i.e., data and/or power wires) may be provided between the alternatesystem and the OMS 100. For example, the OMS 100 may be connected to thevehicle's electronic control unit (ECU) by one or more wires extendingbetween the ECU unit and the vehicle occupant imaging system 109 of theOMS 100. Furthermore, in certain implementations, the steering anglesensor 128 is electrically coupled to the processing unit 200.

When the logical operations described herein are implemented insoftware, the process may execute on any type of computing architectureor platform. For example, the functions of the OMS 100 may beimplemented on any type of computing architecture or platform.

The implementation shown in FIG. 5 illustrates computingdevice/processing unit 200 upon which implementations disclosed hereinmay be implemented. The processing unit 200 can include a bus or othercommunication mechanism for communicating information among variouscomponents of the processing unit 200. In its most basic configuration,processing unit 200 typically includes at least one processor 202 andsystem memory 204. Depending on the exact configuration and type ofcomputing device, system memory 204 may be volatile (such as randomaccess memory (RAM)), non-volatile (such as read-only memory (ROM),flash memory, etc.), or some combination of the two. This most basicconfiguration is illustrated in FIG. 5 by a dashed line 206. Theprocessor 202 may be a standard programmable processor that performsarithmetic and logic operations necessary for operation of theprocessing unit 200.

The processing unit 200 can have additional features/functionality. Forexample, the processing unit 200 may include additional storage such asremovable storage 208 and non-removable storage 210 including, but notlimited to, magnetic or optical disks or tapes. For example, theprocessing unit 200 may be configured for storing at least a portion ofthe image signals received to one or more of the storage 208, 210. Inone implementation, the image signals (or a portion thereof) may bestored on the non-removable storage 210 so as to keep the image signalssecure. In addition, the image signals may be stored and/or transmittedin full or as a set of data related to portions of the image signals,such as data related to occupant information parameters described below.

In addition, the processing unit 200 may be configured for storingfeature information related to image signals captured of at least onevehicle occupants just prior to the vehicle being turned off. Thisfeature information may be stored in a temporary memory area that may bepart of storage 210, for example, or is separate from storage 210. Whenthe vehicle is started up again, the feature information may beretrieved by the processing unit 200 to accelerate startup of the OMS100. In some implementations, the feature information may be stored forone or more of the prior vehicle shut downs. In one implementation,storing feature information for several of the prior vehicle shut downsincreases the likelihood that the feature information stored includesinformation related to the at least one of the occupants in the vehicleat the next start up.

The processing unit 200 can also contain network connection(s) via anetwork interface controller 216 that allow the device to communicatewith other devices. The processing unit 200 can also have inputdevice(s) 214 such as a keyboard, mouse, touch screen, antenna or othersystems configured to communicate with the OMS 100, imaging unit 108,light source 122, and/or steering angle sensor 128 in the systemdescribed above, etc. Output device(s) 212 such as a display, speakers,printer, etc. may also be included. The additional devices can beconnected to the bus in order to facilitate communication of data amongthe components of the processing unit 200.

The processor 202 can be configured to execute program code encoded intangible, computer-readable media. Computer-readable media refers to anymedia that is capable of providing data that causes the processing unit200 (i.e., a machine) to operate in a particular fashion. Variouscomputer-readable media can be utilized to provide instructions to theprocessor 202 for execution. Common forms of computer-readable mediainclude, for example, magnetic media, optical media, physical media,memory chips or cartridges, a carrier wave, or any other medium fromwhich a computer can read. Example computer-readable media can include,but is not limited to, volatile media, non-volatile media andtransmission media. Volatile and non-volatile media can be implementedin any method or technology for storage of information such as computerreadable instructions, data structures, program modules or other dataand common forms are discussed in detail below. Transmission media caninclude coaxial cables, copper wires and/or fiber optic cables, as wellas acoustic or light waves, such as those generated during radio-waveand infra-red data communication. Example tangible, computer-readablerecording media include, but are not limited to, an integrated circuit(e.g., field-programmable gate array or application-specific IC), a harddisk, an optical disk, a magneto-optical disk, a floppy disk, a magnetictape, a holographic storage medium, a solid-state device, RAM, ROM,electrically erasable program read-only memory (EEPROM), flash memory orother memory technology, CD-ROM, digital versatile disks (DVD) or otheroptical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices.

In an exemplary implementation, the processor 202 can execute programcode stored in the system memory 204. For example, the bus can carrydata to the system memory 204, from which the processor 202 receives andexecutes instructions. The data received by the system memory 204 canoptionally be stored on the removable storage 208 or the non-removablestorage 210 before or after execution by the processor 202.

The processing unit 200 typically includes a variety ofcomputer-readable media. Computer-readable media can be any availablemedia that can be accessed by the processing unit (200) and includesboth volatile and non-volatile media, removable and non-removable media.Computer storage media include volatile and non-volatile, and removableand non-removable media implemented in any method or technology forstorage of information such as computer readable instructions, datastructures, program modules or other data. System memory 204, removablestorage 208, and non-removable storage 210 are all examples of computerstorage media. Computer storage media include, but are not limited to,RAM, ROM, electrically erasable program read-only memory (EEPROM), flashmemory or other memory technology, CD-ROM, digital versatile disks (DVD)or other optical storage, magnetic cassettes, magnetic tape, magneticdisk storage or other magnetic storage devices, or any other mediumwhich can be used to store the desired information and which can beaccessed by the processing unit 200. Any such computer storage media canbe part of the processing unit 200.

It should be understood that the various techniques described herein canbe implemented in connection with hardware or software or, whereappropriate, with a combination thereof. Thus, the methods, systems, andassociated signal processing of the presently disclosed subject matter,or certain aspects or portions thereof, can take the form of programcode (i.e., instructions) embodied in tangible media, such as floppydiskettes, CD-ROMs, hard drives, or any other machine-readable storagemedium wherein, when the program code is loaded into and executed by amachine, such as a computing device, the machine becomes an apparatusfor practicing the presently disclosed subject matter. In the case ofprogram code execution on programmable computers, the computing devicegenerally includes a processor, a storage medium readable by theprocessor (including volatile and non-volatile memory and/or storageelements), at least one input device, and at least one output device.One or more programs can implement or utilize the processes described inconnection with the presently disclosed subject matter, e.g., throughthe use of an application programming interface (API), reusablecontrols, or the like. Such programs can be implemented in a high levelprocedural or object-oriented programming language to communicate with acomputer system. However, the program(s) can be implemented in assemblyor machine language, if desired. In any case, the language can be acompiled or interpreted language and it may be combined with hardwareimplementations.

In some implementations, the system memory 204 includescomputer-executable instructions stored thereon that, when executed bythe processor 202, can be used to direct operation of the OMS 100 tomonitor the driver (e.g., capture an image of the driver), determine adriver state, and provide an output signal based on the determineddriver state. For example, the processor 202 can direct operation of theimaging unit 108 and/or the light source 122. In particular, the imagingunit 108 can be directed to capture an image of the imaging area 110 andoutput the captured image signal to the processor 202. The imaging unit108 may also be configured for communicating data associated with theimage signal to the processor 202. The processor 202 can analyze theimage signal from the imaging unit 108 to determine information aboutthe operator state and/or identify portions of the image signal that mayprovide information about the operator state.

In other implementations, the processor 202 may communicate all or aportion of the image signal and/or calculated data based on all or aportion of the image signal to another processor(s) disposed remotelyfrom processor 202. The other processor may be configured for using thereceived image signal (or portions thereof) or data to determine adriver or occupant state.

For example, the processor 202 can receive the image signal from theimaging unit 108 and process the image signal to identify an analysisregion. The analysis region can be a region of the imaging area 110associated with the driver, non-driving vehicle occupant and/or otherregion of interest within or external to the vehicle. Identifying theanalysis region can comprise determining the position and/or orientationof the driver's head and/or eyes. The analysis region can comprise thedetermined position of the driver's head and/or eyes.

The analysis region can be analyzed by the processor 202 (or anotherprocessor) to determine an occupant information parameter. The occupantinformation parameter can include, for example, information about theoccupant corresponding to the occupant's alertness and/or attention or astate of the occupant or vehicle that would prevent the imaging unit 108from capturing relevant data associated with the occupant. The occupantinformation parameter can include the position and/or orientation (e.g.,yaw, pitch, roll) of the occupant's head, the rate of movement of theoccupant's head, the dimensions of the occupant's head, determination ifthe occupant is wearing a certain article that can affect the imagesignal (e.g., a hat, glasses, sunglass, contact lenses, makeup, jewelry,etc.), movement of the occupant's mouth (e.g., determining if theoccupant is talking, yawning, singing, sneezing, etc.), movement of theoccupant's nose (e.g., determining if the occupant is breathing,sneezing, etc.), movement of the occupant's eyes (e.g., squinting,blinking, blink rate, saccades, smooth pursuit movements, vergencemovements, vestibule-ocular movements, etc.), movement and/or positionof the occupant's eye lids, gaze vector, heart rate, workload, occupantidentification features, occupant age estimates, facial musculaturemovements (e.g., movements associated with expression, pain, squinting,blinking, talking, sneezing, singing, sleeping, physical impairment,etc.), and/or the position and/or orientation of the occupant's eyes.Accordingly, the analysis region can be analyzed to determine adeviation in the position and/or orientation of the occupant's headand/or eyes from a predetermined position.

One or more of the occupant information parameters can be analyzed todetermine an occupant state. The occupant state can include, forexample, whether the occupant's eyes are open or closed, whether or notthe occupant is looking at the road, the center console, or elsewhere,whether or not the occupant is distracted, the relative alertness of theoccupant, the occupant's emotion(s) (e.g., angry, sad, happy, excited,nervous, afraid, etc.), the occupant's physical condition (e.g., sleepy,hungry, ill, impaired, etc.), and/or the occupant's demeanor (e.g.,posture, eating, drinking, giving verbal commands, completing manualtasks, direction of eye gaze, interested, etc.), and the like.Accordingly, analyzing the occupant information parameter to determinethe occupant state can include determining that the position and/ororientation of the occupant head and/or eyes are deviated from apredetermined position. Analyzing the occupant information parameter mayalso include determining that the position and/or orientation of theoccupant head and/or eyes are deviated from the predetermined positionfor at least a predetermined amount of time. Other examples include,assessing the occupant's visual distraction level (e.g., occupant state)through monitoring the occupant's eye/pupil vectors relative to theposition of the windshield (e.g., occupant information parameter).Features of the mouth, such as corners and average separation of thelips, can be monitored to determine when a particular occupant isspeaking, and audio signals captured in the vehicle may be correlatedwith the mouth features by a speech recognition system (e.g., such asused in hand's free processing systems) to filter out speech fromunintended occupants and/or background noise. Monitoring the motion ofthe noise and/or mouth can be used to infer an estimate of respirationrate, which can be used, for example, to assess if the occupant hasstopped breathing, or if respiration rate is elevated, which can occurduring certain perturbed emotional states or medical emergencies.Monitoring the luminance of the face can be used to assess theappearance of sweat beads, which can be used to assess the occupant'scomfort (e.g., determine if the climate controls should be adjusted)and/or fitness level (e.g., occupant is ill and/or experiencing amedical event). In addition, the intensity of the light source 122 maybe altered to compensate for ambient light, to minimize the visibilityof the light source 122, and/or to adjust for the skin tone of theoccupant within the imaging area. Spectral analysis of the signalcollected from the camera can be used to derive and/or estimatephysiological response such as skin heating/cooling and/orelectrocardial activity and rates. A wide range of occupant informationparameters can be monitored to derive or estimate a wide range ofoccupant states, which, for example, can be used to establish uniquehealth and behavior characteristics for individual occupants that canenhance the safety, health, comfort and convenience of the driver andother occupants.

In certain implementations, the processor 202 can output a signal basedon the occupant state. In some implementations, the output signal can bethe image signal corrected for the angle of rotation of the steeringwheel assembly 104 and/or the rate of angular rotation of the steeringwheel assembly 104. The output signal can also be instructions to adjustthe imaging unit 108 to correct for the angle of rotation of thesteering wheel assembly 104 and/or the rate of angular rotation of thesteering wheel assembly 104, as discussed above. The output signal(s)can also be used by other vehicle systems to establish baseline occupantcharacteristics (e.g., health, attention, behavior), establishthresholds for actuating other vehicle systems (e.g., control, warningsystems), and provide real-time occupant state features that can becompared against actuation thresholds.

The output signal can comprise an electrical signal, a wifi signal, orthe like. The output signal can be output to another vehicle system toprovide information about the occupant state to that vehicle system. Insome implementations, the output signal can be provided to anothervehicle system that can, for example, change vehicle parameters based onthe driver state (e.g., adjust the sensitivity of the steering wheel,brakes and/or accelerator, turn on or off music, adjust the volume ofmusic, change the type of music, turn on/off interior lights, adjust thecabin temperature, inject a smell, adjust the wavelength and/orintensity of light being emitted by the light source 122, reduce orremove degrees of freedom for the operation of the vehicle from thedriver, notify emergency services, modify thresholds of automation,etc.).

And, in some implementations, the output signal may include instructionsfor OMS 100 or another vehicle system to illuminate or alter theintensity of a light source, play a sound, and/or provide tactilefeedback to the driver or other occupant via a haptic feedback device(e.g., vibration, heat, cooling, etc.). The light, sound, and/or hapticfeedback may be used to warn the driver or other occupant, for example.In one implementation, the light to be illuminated may include a lightbar system, which may part of or the same light bar 124 described aboveor a separate light bar disposed on another portion of the steeringwheel assembly or elsewhere in the vehicle. Exemplary light bar systemsare described in co-pending U.S. patent application Ser. No. 14/061,397entitled “Steering Wheel Light Bar” and filed on Oct. 23, 2013, Ser. No.14/061,383 entitled “Steering Wheel Light Bar” and filed on Oct. 23,2013, and Ser. No. 14/061,408 entitled “Steering Wheel Light Bar” andfiled on Oct. 23, 2013 and U.S. provisional patent application62/027,969 entitled “Steering Grip Light Bar Systems” filed Jul. 23,2014. These four applications are hereby incorporated by reference intheir entirety. The haptic feedback device may include a heater paddisposed around the rim of steering wheel assembly or a vibratoryexciter (e.g., a speaker) disposed within the rim or hub of the steeringwheel assembly, for example.

Before, after and/or during analysis of the image signal received fromthe imaging unit 108, the processor 202 can be used to adjust theimaging unit 108 and/or received image signal based on the status of thesteering wheel assembly 104. The processor 202 may also be used toadjust the light source 122 based on the status of the steering wheelassembly 104. As will be described in more detail below, the processor202 can analyze an electrical signal from the steering angle sensor 128to obtain information about the angle of rotation of the steering wheelassembly 104 and/or the rate of angular rotation of the steering wheelassembly 104 and adjust the imaging unit 108 image signal based on thatinformation. For example, the processor 202 can receive an electricalsignal from the steering angle sensor 128 and process the electricalsignal to identify the orientation/angle of rotation of the steeringwheel assembly and/or the rate of angular rotation of the steering wheelassembly. The received signal from the steering angle sensor 128 may beanalyzed to adjust the imaging unit 108 and/or the image signal tocompensate for the angle of rotation of the steering wheel assembly 104and/or the rate of angular rotation of the steering wheel assembly 104.For example, the imaging unit 108 may be adjusted to rotate or zoom inor out based on the signal from the steering angle sensor 128. Inanother example, the image signal captured that corresponds to theimaging area 110 may be adjusted to correct for the angle of rotation ofthe steering wheel assembly 104 and/or the rate of angular rotation ofthe steering wheel assembly 104.

Adjusting the imaging unit 108 and/or light source 122 to correct forthe angle of rotation of the steering wheel assembly 104 and/or the rateof angular rotation of the steering wheel assembly 104, can include, forexample, accounting for a change in geometry between the imaging unit108 and the occupant, such as the driver, adjusting the shutter speedand/or frame rate of the camera 120, adjusting the intensity of thelight being emitted from the light source 122, adjusting which lightsource 122 is active at a given time, adjusting the angle of the cameralens, adjusting the gain, focus and/or optical filter of the camera 120,adjusting the wavelength or range of wavelengths of light emitted fromthe light source 122, and the like, or a combination thereof.

The image signal captured that corresponds to the imaging area 110 canalso be adjusted to correct for the angle of rotation of the steeringwheel assembly 104 and/or the rate of angular rotation of the steeringwheel assembly 104. Adjusting the image signal can include, for example,adjusting the contrast of the image signal, adjusting the orientation ofthe image signal, adjusting the gain of the image signal, accounting fora change in geometry between the imaging unit and the driver or otheroccupant (e.g., transforming the coordinate system of the image signal),accounting for distortion and/or blur in the image signal, and the like.

The analysis of the image signal from the imaging unit 108 and/or theelectrical signal output from the steering angle sensor 128 is describedabove as being carried out by processor 202. However, in otherimplementations, the functions described above may be carried out inwhole or in part on one or more additional processors and/or processingunits. For example, the OMS 100 can comprise one or more additionalprocessing units and/or processors.

In some implementations, the OMS 100 can further comprise a disablingunit configured to temporarily disable all or some of the OMS 100operations when a driver signal is received. The driver signal can beindicative of the driver performing some operation that would preventproper operation of the OMS 100. The driver signal can include, forexample, a signal output upon rotation of the steering wheel assembly104 of the vehicle by at least a predetermined amount and/or for apredetermined amount of time. For example, the driver signal can beoutput when the driver rotates the steering wheel assembly 104 to turnthe vehicle. The signal indicating rotation of the steering wheelassembly 104 can, for example, be obtained from the steering wheelassembly angle sensor 128. The driver signal can, in someimplementations, cease to be output when the steering wheel is returnedto a substantially central position for at least a predetermined amountof time. For example, the driver signal can cease to be output when thedriver has completed the turn of the corner and resumed normal driving.

The rate and/or angle of rotation of the steering wheel assembly canalso be determined by analyzing sequential signals from the camera tomonitor the change in position of reliable, fixed features of thevehicle within the imaging area 110 (e.g., position of doors, positionof windows, position of roof). Furthermore, such reliable, fixedfeatures can be added to the vehicle within the imaging area to functionas reference features to be used by the OMS 100. For example, opticallytransparent, but IR visible symbols or shapes can be placed on thevehicle seat, headliner, and/or seat belt, in an a priori pattern, whichcan be used by the OMS 100 to derive the angle of rotation of thesteering wheel assembly.

In some implementations, the OMS 100 can communicate data through anautomotive clock spring, such as the automotive clock spring 50described in relation to FIGS. 6-9 below. Exemplary automotive clocksprings include a rotary-type electrical connection that permitsrotation of the rotatable portion of the steering wheel assembly 104while maintaining an electrical connection between vehicle systemcomponents disposed on the rotating portion of the steering wheelassembly 104 and components disposed outside of the rotating portion. Incertain implementations, the automotive clock spring can be used toelectrically couple the imaging unit 108 to at least one other vehiclesystem during rotation of steering wheel assembly 104. Furthermore, theclock spring can also electrically couple the imaging unit 108, thelight source 122, and the steering angle sensor 128 to a power source,such as the vehicle battery, and/or a processing unit 200 disposedoutside of the rotating portion of the steering wheel assembly.

FIGS. 6-10 illustrate various implementations of automotive clock spring50 that may be electrically coupled to the vehicle occupant imagingsystem 109. In particular, FIG. 6 illustrates a front view of theautomotive clock spring 50. The clock spring 50 includes a rotor 54 anda stator 52. The rotor 54 is fixed relative to the rotatable portion ofthe steering wheel assembly 104. In the implementation shown in FIG. 6,the rotor 54 includes a central aperture 55 for receiving the steeringshaft 107 to couple the rotor 54 to the steering shaft 107. The steeringshaft 107 and the rotor 54 are configured to rotate together about axisB, which extends through the aperture 55. The stator 52 is disposedradially outwardly of the rotor 54 and is statically coupled to thesteering column 106 or another non-rotating portion of the steeringassembly 104.

The clock spring 50 further includes processor 202 a disposed in therotor 54, processor 202 b disposed in the stator 52, steering anglesensor 128 disposed in the stator 52, a set of wires 58 extendingbetween and electrically coupling processors 202 a and 202 b, electricalconnectors 56 a, 56 b disposed on a face of a housing of the rotor 54,wires 62 a, 62 b extending between the electrical connectors 56 a, 56 b,respectively, and the processor 202 a, and an electrical connector 60disposed on a face of a housing for the stator 52.

In the implementation shown in FIG. 6, the steering angle sensor 128 isdisposed in the housing of the stator 52. The steering angle sensor 128is electrically coupled to the set of wires 58 that electrically couplethe processors 202 a and 202 b. Thus, the angle of rotation or rate ofangular rotation captured by the steering angle sensor 128 may beelectrically communicated to the processor 202 a or processor 202 b viawires 58. According to other implementations (not shown), as notedabove, the steering angle sensor 128 may be disposed in the housing ofthe rotor 54 or between another set of non rotating and rotatingcomponents of the steering wheel assembly.

The implementation in FIG. 6 also includes electrical connectors 56 a,56 b disposed on the face of the housing of the rotor 54. The connectors56 a, 56 b are configured for receiving mating connectors from theimaging unit 108 and light source 122, which, as described above, aredisposed on a rotating portion of the steering wheel assembly 104. Inone implementation, the electrical wires from the imaging unit 108 andlight source 122 may be routed to the electrical connectors 56 a, 56 bthrough the steering shaft 107 to keep the wires hidden and out of theway of the vehicle operator. The connectors 56 a, 56 b allow for moreefficient installation of the imaging unit 108 and the light source 122onto the steering wheel assembly 104. Furthermore, although only twoconnectors 56 a, 56 b are shown in FIG. 6, in other implementations,there may be one or more than two connectors. For example, there may bean electrical connector for each imaging unit 108 and light source 122of the OMS 100.

In some implementations, such as shown in FIG. 9, the connectors 56 a,56 b are coupled to the processor 202 a via lengths of insulated,electrical wires 86 a, 86 b that extend out of the face of the housingof the rotor 54 (e.g., pigtails) toward the rotation portion of thesteering wheel assembly 104.

The set of electrical wires 58 may be coupled adjacent each other via aflat tape 59 that includes the electrical wires 58 separated by adielectric material 57. The electrical tape 59 is configured to wrap andunwrap around the rotor 54 during rotation of the steering wheelassembly without losing a connection between the processors 202 a, 202 band without breaking the wires within the tape 58. The image signals orcalculated data electrically communicated through the wires 58 of thetape 59 may also be communicated to another processing unit 200 of theOMS 100 disposed outside of the clock spring 50 or another vehiclesystem disposed outside of the clock spring 50 via the electricalconnector 60 disposed on the housing of the stator 52. The statorconnector 60 and the wires 58 of the tape 59 may also be used toelectrically communicate data and/or signals between components mountedon the rotating portion of the steering wheel and other vehicle systems,such as cruise control, air bag and vehicle safety systems, steeringheating control, audio and user communication systems, and the dynamicstability control system. Furthermore, processed image signals and/ordata related thereto may be communicated by processor 202 a and/or 202 bto other vehicle systems, such as, for example, vehicle safety systems,user communication systems, and in-vehicle and external passive sensors(e.g., passenger/driver occupant sensor(s), rear occupant sensor(s),reverse camera, external radars, etc.). And, in a furtherimplementation, processor 202 a and/or 202 b may receive data from theseother vehicle systems. The data received by the processor 202 a and/or202 b may be used by the processor 202 a, 202 b to identify whichportions of the image signal should be selected and processed furtherand/or communicated to these systems or other vehicle systems.

The depth of the clock spring 50 may be increased as compared toconventional clock springs to accommodate the addition of one or more ofprocessors 202 a, 202 b into the clock spring 50, according to certainimplementations. For example, in one implementation, the depth of theclock spring 50, which extends in a direction parallel to the rotationalaxis of the rotor 54, is increased from about 30 millimeters to betweenabout 60 and about 70 millimeters. The diameter of the clock spring 50is kept generally the same as convention clock springs so as to fitwithin the steering column 106 of the vehicle.

In one implementation, the tape 59 may include eight wires 58, ortraces, laid out side by side and separated by dielectric material 57.The dielectric material 57 shields the wires 58 from electricalinterference with each other and other components in the clock spring 50and steering column 106. The tape 59 is wound tightly around the rotor54 about 3.5 turns to allow the steering wheel assembly 104 to berotated and the tape 59 to unwind and wind with the rotation of thesteering wheel assembly 104. However, in other implementations, the tape59 may include more than or less than eight wires 58 and may be woundone or more turns around the rotor 54, depending on the anticipatedrotational movement of the steering wheel assembly 104. In addition,there may be more than one tape 59 extending between the rotor 54 andthe stator 52. Generally, the number and nature of the wiring is basedon wire gauge and/or the type of components mounted on the rotatableportion of the steering wheel assembly 104, such as, for example, theOMS 100 components, driver air bag system, steering wheel heatingsystem, human machine interface systems (e.g., switches and/or touchsensitive surfaces configured for receiving input from a user), thelight bar feedback system, and the horn.

Processors 202 a and 202 b each include a plurality of stacked,arcuate-shaped, printed circuit boards. The arcuate shape of theprocessor 202 a, 202 b allows them to fit within the rotor 54 and stator52 of the clock spring 50 without interfering with the rotation of therotor 54 and movement of the wires 58 between the rotor 54 and stator52. And, stacking the printed circuit boards provides sufficient surfacearea for the processors 202 a, 202 b to perform the functions describedherein. However, in other implementations, there may be only onearcuate-shaped printed circuit board or the printed circuit boards maybe flat and/or not stacked.

Processors 202 a and 202 b are similar to processor 202 and separatelyor together may perform one or more functions of processor 202 describedabove, according to various implementations. The functions to beperformed by each processor 202 a, 202 b, may be selected based onseveral factors, including, for example, the rate at which the imagesignals are being captured, the size of the image signals, the number ofimaging units 108 and light sources 122 disposed on the rotating portionof the steering wheel assembly 104, and the ability of the housingand/or the steering wheel assembly 104 to dissipate thermal energy fromthe heat generating components. For example, in certain implementations,the processor 202 a may be configured for electrically receiving imagesignals captured by the imaging unit 108 and selecting at least aportion of the image signals for communicating to the processor 202 b;electrically receiving at least one of an angle of rotation or rate ofangular rotation of the steering wheel assembly 104 from the steeringangle sensor 128 and adjusting an orientation of the image signals basedon the received angle of rotation or rate of angular rotation;electrically receiving at least one of an angle of rotation or rate ofangular rotation of the steering wheel assembly 104 from the steeringangle sensor 128 and adjusting the imaging unit 108 based on thereceived angle of rotation or rate of angular rotation; compressing theselected image signals prior to communicating the image signals to theprocessor 202 b; controlling an amount of light emitted from the lightsource 122; and saving at least a portion of the selected image signalsto a memory. In some implementations, selecting at least a portion ofthe image signals for communicating to the processor 202 b includesidentifying and selecting one or more portions of the image signalrelated to one or more occupant information parameters.

Furthermore, in certain implementations, the memory may be disposed onthe printed circuit board(s) in the rotor 54, elsewhere in the rotor 54,outside of the rotor 54 (e.g., in the stator 52 or in another portion ofthe vehicle), or a combination thereof.

In other implementations, the processor 202 a may be configured forselecting at least a portion of the image signals related to occupantinformation parameters, calculating data from the selected signals, andcommunicating the calculated data to the processor 202 b.

In yet another implementation, which is shown schematically in FIG. 10,a processor 202 c may be disposed adjacent the imaging unit 108. Thisprocessor 202 c may be configured for electrically receiving imagesignals captured by the imaging unit 108 and selecting at least aportion of the image signals for communicating to processor 202 a and/orcalculating data from the selected signals.

In addition, in an implementation in which processor 202 a is configuredfor compressing the image signal prior to communicating the image signalto processor 202 b, processor 202 b may be configured for decompressingthe compressed image signals.

Although FIGS. 6 and 9 illustrate the light source 122 as beingelectrically coupled to the processor 202 a, one or more light sources122 may instead be coupled to and controlled by the processor 202 b viawires 58 or to other processors disposed in the rotor 54 and/or stator52, according to other implementations (not shown). For example, one ofthe connectors 56 a, 56 b may be coupled to processor 202 b via wire 62b or 86 b and wires 58 such that the light source 122 that is coupled tothe connector 56 a, 56 b is electrically coupled to the processor 202 b.In such an implementation, the processor 202 b is configured forcontrolling the light source 122.

As noted above, processor 202 a may be configured for identifying andselecting at least a portion of the image signals related to one or moreoccupant information parameters for communicating to the processor 202b. In certain implementations, the processor 202 b is further configuredfor smoothing, filtering, and/or analyzing the received image signals.

Processors 202 a and 202 b may also be electrically coupled to a powersource disposed within the vehicle via the stator connector 60 and wires58. Power from the power source is available to the imaging unit 108 andthe light source 122 via one or more of the processors 202 a, 202 baccording to certain implementations. In other implementations (notshown), power may be available directly to the imaging unit 108 andlight source 122 via individual wires coupled to wires 58.

In some implementations, if the physical size of processor 202 a issufficient to throw the rotation of the rotor 54 off balance, a counterbalance may be included in the rotor 54 opposite the processor 202 a tobalance the rotational momentum of the rotor 54.

Various implementations provide an improved packaging solution for imagedetection systems within a vehicle. In particular, by processing theimage signal in processor 202 a disposed within the rotor 54 of theclock spring 50, the raw image signal from the imaging unit 108 isreceived and processed closer to the imaging unit 108, which preventsloss or interference with the signal that may occur over longerdistances between the imaging unit 108 and the processor. Thisarrangement also allows for efficient communication of the image signalsused for determining occupant information parameters, which improves theoperation of the occupant monitoring system 100. In particular, if theimaging unit 108 is configured to capture image signals at a rate of 60frames per second, the processor receiving the image signals would needto process 20 megabytes of data every 10 seconds. Such requirementscould require a processor that is physically too large to install withina typical clock spring. Furthermore, there are too few wires withintypical clock springs to accommodate the transmission at that datatransmission rate. Thus, various implementations overcome theseconstraints by including a first processing unit in the rotor that isconfigured for selecting at least a portion of the image signalsreceived and communicating the selected portion of image signals (orcalculated data from the selected portion of image signals) to a secondprocessing unit outside of the rotor for further processing andanalysis.

FIG. 10 illustrates a schematic flow of signals and/or data betweenvarious components of the OMS 100 and other vehicle systems through theclock spring 50, according to various implementations. In particular,the light source 122 and the imaging unit 108 are disposed on therotating portion of the steering wheel assembly 104 and are electricallycoupled to processor 202 a disposed on the rotor 54. Other vehiclesystems, such as human machine interface systems (e.g., touch pad(s),touch sensitive areas on the steering wheel assembly, and/or switchesfor interfacing with one or more vehicle systems, such as HVAC, audio,user communication, etc.), heater system for heating the steering wheel,horn activation, and the driver airbag system, may also be disposed onthe rotating portion of the steering wheel assembly 104. These systemsmay be in communication with other processors disposed outside of therotor 54 via wires 58 extending between the rotor 54 and the stator 52or in communication with processor 202 a and/or 202 b. Furthermore, asnoted above, the processor 202 a or processor 202 b may be furtherconfigured for controlling the light source 122. Or in otherimplementations as depicted by the dotted lines shown in FIG. 10, aseparate processor may be disposed in the rotor 54 or stator 52 forcontrolling the light source 122. Furthermore, signals and/or data fromthe processors 202 a, 202 b or other processors disposed in the rotor 54and/or stator 52 and from other systems disposed on the rotating portionof the steering wheel assembly 104 may be communicated to vehicle-sideprocessing units, such as the processing unit(s) of the OMS 100, forfurther analysis and/or processing.

Although the implementations described above describe the clock spring50 as used with components of the OMS 100, clock spring 50 may becoupled to other data acquisition systems and/or systems acquiringsignals having a relatively high bandwidth. For example, in variousimplementations, at least one data acquisition unit may be mounted on arotatable portion of a vehicle steering wheel assembly that is rotatableabout a steering column. The first processing unit disposed within therotor is configured for electrically receiving signals captured by thedata acquisition unit and selecting at least a portion of the signalsfor communicating to a second processing unit. The second processingunit is disposed outside of the rotor in the vehicle (e.g., in thestator or outside of the stator) and is electrically coupled to the setof electrical wires extending between the rotor and the stator. Theselected signals are electrically communicated through the set ofelectrical wires.

In other implementations, such as shown in FIGS. 11A and 11B, a slipring SR may be used instead of a clock spring to route electrical wiresextending between the rotatable portion of the steering wheel assembly104 and the non-rotatable portions of the steering wheel assembly and/orsteering column 106. The slip ring SR includes a rotor portion R and astator portion S. The rotor portion R is coupled to the rotating portionof the steering wheel assembly 104 and defines a hollow shaft Hrextending around its axis of rotation C. The rotor portion R is engagedwithin a hollow shaft Hs of the stator portion S such that the rotorportion R can rotate within the hollow shaft Hs of the stator portion Sabout the axis of rotation C. The stator portion S is coupled to astationary portion of the steering wheel assembly 104 or steering column106. The rotor portion R may also include an annular lip A that extendsradially outwardly from one end of the rotor portion R and axiallyengages an outer axial end E of the stator portion S to prevent axialmovement of the rotor portion R relative to the stator portion S. Theelectrical wires from components of the OMS 100 and other systems thatmay be disposed on the rotatable portion of the steering wheel assemblyextend through the hollow shaft Hr of the rotor portion R and areconfigured to rotate with the rotor portion R.

In some implementations, the OMS 100 can be constructed as a singlemodular unit. For example, the single modular unit can be aself-contained unit including the camera 120, light source 122, and/orthe processing unit 200 or a portion thereof. When constructed as asingle modular unit, the OMS 100 can be conveniently packaged andconveniently installed in any steering wheel assembly 104. The singlemodular unit can be coupled to the steering wheel assembly 104 using anysuitable fastening mechanism, such as, for example, screws, hooks,clips, or any other form of mechanical fastener known in the art, oradhesive (e.g., gluing), soldering, welding, or any other fasteningtechnique known in the art. Configuring the OMS 100 as a single modularunit can allow for commonization of the electronics (e.g., integration)and therefore faster electronic communication.

FIGS. 12-20 show various implementations of how various components ofthe OMS 100 may be coupled to the steering wheel assembly 104. Inparticular, according to the implementation shown in FIGS. 12-15, theOMS 100 includes a mounting bracket 301, a housing 303, a lens 305, andimaging unit 108. The mounting bracket 301 includes a body 355 to whichthe imaging unit 108 is coupled and mounting tabs 353, 354 that extendfrom a lower edge of the body 355. Each tab 353, 354 defines an opening351, 352, respectively, that aligns with openings defined in an upperarea of the frame of the hub 116 of the steering wheel assembly 104.Each set of aligned openings receives a screw 350 to secure the mountingbracket 301 to the hub 116. However, in other implementations, themounting bracket 301 may be attached to the steering wheel assembly 104such that it extends upwardly from the central portion 112 using othersuitable fastening mechanisms, such as, for example, hooks, clips, orany other form of mechanical fastener known in the art, or adhesive(e.g., gluing), soldering, welding, or any other fastening techniqueknown in the art.

The mounting bracket 301 may be formed of aluminum, a magnesium alloy,steel or other suitable material capable of supporting the OMS 100components and transferring at least a portion of the heat generatedfrom the components to the frame of the steering wheel assembly 104. Themounting bracket 301 may also be integrally formed or molded with thecentral portion 112 of the steering wheel assembly 104.

The housing 303 includes a back surface 304 that is disposed adjacent tothe back cover 126 of the steering wheel assembly 104, an upper surface323 that extends transversely to the back surface 304, and side surfaces324 that extend downwardly from side edges of the upper surface 323 andtransversely from the back surface 304. The back surface 304, sidesurfaces 324, and upper surface 323 define an area therebetween that isconfigured for fitting around at least a portion of the body 355 of themounting bracket 301. The upper surface 323 may include fins 325 thatextend in the direction from a front perimeter of the housing 303 to theback surface 304 and are distinct and spaced apart from each other inthe direction between the side surfaces 323. These fins 325 provide moresurface area so as to be a more effective heat sink and providestructural reinforcement for the upper surface 323 of the housing 303.

In the implementation shown in FIG. 17B, the back surface 304 fits flushwith, or within the same plane as, the back cover 126 of the steeringwheel assembly 104. However, in the implementations shown in FIGS. 18Band 19B, the back surfaces 304′, 304″, respectively, are not flush withthe back covers 126′, 126″, respectively, but are disposed in a planethat is spaced inwardly (toward the front of the assembly 104′, 104″,respectively) from the plane that includes the back covers 126′, 126″.

In the implementations shown in FIGS. 12-15 and 17A, the upper surface323 and side surfaces 324 of the housing 303 define a substantiallyrectangular shaped perimeter. The perimeter may be slightly arcuateshaped along the upper surface 323 and/or have rounded corners betweenthe upper 323 and side surfaces 324 to blend in aesthetically with thesteering wheel assembly 104.

However, in the implementation shown in FIGS. 18A-18B, the upper surface323′ of the housing 303′ defines a perimeter that includes a rounded,semi-circular central portion 380 that extends upwardly from thesteering wheel assembly 104′, and the side surfaces 324′ of the housing303′ are angled or skewed toward each other and the central portion 380.This shape may blend in aesthetically with the shape of steering wheelassembly 104′ shown in FIGS. 18A and 18B. And, in the implementationshown in FIGS. 19A and 19B, the upper surface 323″ of the housing 303′defines a perimeter that includes a trapezoidal shaped central portion385 that extends upwardly from the steering wheel assembly 104″. Sidesurfaces 324″ of the housing 303″ are angled or skewed toward each otherand the central portion 385. This shape may blend in aesthetically withthe shape of the steering wheel assembly 104″ shown in FIG. 19A.

The imaging unit 108 is coupled to the mounting bracket 301 adjacent acentral portion of the body 355 of the mounting bracket 301. In theimplementation shown in FIGS. 13A-15, the imaging unit 108 is camera 120that includes a lens 320, such as, for example, an adjustable lens or afixed lens. The camera lens 320 is disposed at a distal end of thecamera 120, and light enters the camera 120 via the lens 320. In theimplementation shown in FIG. 14, the camera lens 320 is secured to thecamera 120 using at least one side set screw 375, and camera 120 iscoupled to the mounting bracket 301 using screws 376. However, as notedabove, other types of imaging units may be used in otherimplementations, and other fastening mechanisms may be used to couplethe camera 120 to the mounting bracket 301 and/or within the housing303.

In addition, in some implementations, the light source 122 is coupled tothe mounting bracket 301 and is disposed adjacent the imaging unit 108.For example, in the implementation shown in FIGS. 13A-15, the lightsource 122 includes two printed circuit boards 352 each having fourpairs of LEDs 354 disposed thereon. One of the printed circuit boards352 is coupled to the mounting bracket 301 on a right side of theimaging unit 108, and the other printed circuit board is coupled to themounting bracket 301 on a left side of the imaging unit 108. A thermalcoupling material 330 configured for transferring heat between theprinted circuit board and the mounting bracket 301 is disposed betweenthe printed circuit board and the mounting bracket 301. The thermalcoupling material 330 may be a thermal coupling pad, such as a foam padhaving thermally conductive materials disposed therein, or a thermalcoupling paste, for example. The pad, for example, may include adhesiveon both sides for attaching to a back surface of the printed circuitboards and a front surface of base 355 of the mounting bracket 301. Inaddition to the adhesive or as an alternative to the adhesive, each padmay define openings that align with openings defined in the printedcircuit board and the mounting bracket for receiving a screw 350 tosecure the pad and the printed circuit board 352 to the mounting bracket301.

In various implementations, the light emitted from the light source 122may internally reflect from the lens 305 or otherwise reach the cameralens 320 or other type of imaging unit 108 before passing through thelens 305. To prevent the light from the light source 122 from enteringthe imaging unit 108 prior to exiting the lens 305, a light blockingmaterial may be disposed between a distal end of the imaging unit 108and the light source 122. For example, as shown in FIG. 15, a ring 322of compressible material, such as a polymeric foam, silicone, rubber,etc., may be extend between a distal end of the camera lens 320 and theback surface 307 of the lens 305. The ring 322 is annular shaped tocorrespond to the outer perimeter of the camera lens 320, but in otherimplementations, the ring 322 may be shaped to correspond to theperimeter of other types of imaging units 108. The compressible materialallows the camera lens 320 to be adjusted (e.g., zoom in or out) in thedirection of the lens 305 while maintaining contact with compressiblematerial. In other implementations, the light blocking material may bedisposed between the printed circuit boards 352 and the lens 305 toprevent light from the LEDs 354 from being received into the imagingunit 108 prior to exiting the lens 305. In other implementations, thelight blocking material may extend between the imaging unit 108 ormounting bracket 301 and the OMS lens 305.

Furthermore, the light blocking material may be secured in positionusing various fastening mechanisms, such as, for example, screws, hooks,clips, or any other form of mechanical fastener known in the art, oradhesive (e.g., gluing), soldering, welding, or any other fasteningtechnique known in the art, a thread (e.g., a DSLR camera filter ring),and/or a combination thereof.

As shown in FIG. 20, the electrical wires coupling the light source 122and the imaging unit 108 to at least one processor and/or power sourcemay be extended from the central portion 112 of the steering wheelassembly 104 through the opening in the back cover 126 configured forcoupling to the steering shaft 106. As noted above, the wires may beelectrically coupled to processor 202 a in the rotor 54, processor 202 bin the stator 52 of the automotive clock spring 50, and/or to one ormore processors disposed outside of the automotive clock spring 50.Furthermore, in some implementations, the wires may be coupled toprocessor 202 c disposed within the housing 301, and the processor 202 cmay be coupled to the mounting bracket 301 or be otherwise disposed inthe housing 301. As noted above, the processor 202 c may be coupled toprocessor 202 a in the rotor 54 of the automotive clock spring 50 and/orthe processor 202 b in the stator 52 of the clock spring 50. And, insome implementations, the processor 202 c may be disposed on one or bothof the printed circuit boards 352 shown in FIG. 14. Furthermore, in oneimplementation (not shown), the OMS 100 may include one printed circuitboard on which the processor 202 c and the light source 122 aredisposed.

The lens 305 includes a front surface 306, a back surface 307 oppositethe front surface 306, an upper perimeter 308, a lower perimeter 310,and side perimeters 309 extending between the upper 308 and lowerperimeters 310. The back surface 307 is disposed facing the imaging unit108, the front surface 306 is disposed facing the interior of thevehicle.

In an implementation in which the imaging unit 108 detects infraredimage signals, the lens 305 may be configured for optically blockingvisible light and allowing infrared light to pass through the lens 305.For example, the lens 305 may be formed from of poly(methylmethacrylate) (PMMA) or other acrylic-like material. In theimplementation shown in FIGS. 12-13B, the lens 305 is formed fromACRYLITE, which is a PMMA, acrylic 1146-0 grade, black materialmanufactured by Evonik Industries. ACRYLITE is opaque to visible lightbut allows the transmission of infrared light starting at about 750nanometers. ACRYLITE also blocks the transmission of ultraviolet light.FIG. 16 illustrates the percentage of light that passes through ACRYLITEat various wavelengths. As shown, no light under about 750 nanometerspasses through the ACRYLITE. The lens 305 may further be cut from asheet of the visible light blocking material or molded to a particularshape.

In other implementations, the lens may be formed from any polycarbonatematerial, such as, for example, polycarbonate (e.g., LEXAN),acrylonitrile butadiene styrene polycarbonate (ABS-PC), PC-ABS,acrylic-styrene-acrylonitrile terpolymer polycarbonate (ASA-PC), orother plastics that include polycarbonate as a major alloying element.In addition, the lens may be formed from glass, cellulose acetatebutyrate (CAB) or butyrate, glycol modified polyethylene terephthalate(PET-G), or other polymers, for example.

Furthermore, in some implementations, an optical film or coating/paintmay be applied to one or both of the back surface 307 or front surface306 of the lens 305 that blocks visible and/or UV light and allowstransmission of infrared light.

The lens 305 shown in FIGS. 12-19B are flat, but in otherimplementations, the lens may be curved.

In the implementations shown in FIGS. 12-19B, a trim piece 340 and alens support piece 360 are used to prevent movement of the lens 305relative to the housing 303 and steering wheel assembly 104. Inparticular, the trim piece 340 includes an upper portion 341 and sideportions 342. The upper portion 341 is shaped to follow the shape of thefront perimeter of the upper portion 323 of housing 303, and the sideportions 342 are shaped to follow the shape of the front perimeter ofside portions 324 of the housing 303. The lens 305 is disposed betweenthe front perimeter of the housing 303 and the trim piece 340 to securethe upper perimeter 308 and side perimeters 309 of the lens 305 frommovement relative to the housing 303. In addition, the lens supportpiece 360 has an elongated body and includes an upper surface 361 thatdefines a channel 362 extending along a length of the elongated body.The lens support piece 360 is disposed adjacent where the mountingbracket 301 is coupled to the steering wheel assembly 104 and extendsbetween the front perimeters of the side portions 342 of the trim piece340. At least a portion of the lower perimeter 310 of the lens 305engages the channel 362 to prevent movement of the lower perimeter 310of the lens 305 relative to the housing 303. The lens support piece 360may also cover a gap between the central hub 116 of the steering wheelassembly 104 and the lower perimeter 310 of the lens 305. However, inother implementations, the lens 305 may be secured to the housing 303without any trim or lens support pieces, it may be secured by single ormultiple trim pieces, or it may be secured by the housing and the lenssupport piece without any trim pieces.

The trim piece 340 includes tabs 344 that extend inwardly from each ofthe side portions 342. Each tab 344 defines an opening 346 that alignswith openings 348 defined through the housing 303 and openings 357defined through the mounting bracket 301. To secure the trim piece 340and the housing 303 to the mounting bracket 301, a screw 350 is engagedthrough aligned openings 346, 348, 357 on each side of the trim piece340, housing 303, and mounting bracket 301.

The trim piece 340 may be formed of a rigid material, such as a plastic,metal, glass, or ceramic material. In addition, in the trim piece 340may be dyed, coated, plated, or painted a particular color. For example,in the implementation shown in FIGS. 12-17B, the trim piece 340 iscoated, plated, or painted with a chrome color. However, in otherimplementations, the trim piece 340 may be colored differently, such ascolored black or grey to match the housing or the steering wheelassembly.

Similarly, the lens support piece 360 may be formed of similar rigidmaterials and may also be dyed, coated, plated, or painted a particularcolor. In addition, the lens support piece 360 may be coupled to themounting bracket 301 via screws, clips, adhesive, or other suitablefastening mechanism. In the implementation shown in FIGS. 12-15, thelens support piece 360 includes bosses 364 that extend from a lowersurface 363 of the lens support piece 360. The bosses 364 defineopenings that align with openings defined in the mounting bracket 301. Ascrew 350 is engaged in the aligned opening in the lens support piece360 and the mounting bracket 301 to secure the lens support piece 360adjacent the mounting bracket 301. In the implementations shown in FIGS.12A through 20, various components of the OMS 100 are coupled to thecentral portion 112 of the steering wheel assembly. By coupling theimaging unit 108 to the central portion 112, such as is described above,the imaging unit 108 is closer to one or more occupants in the vehiclecabin and can thus receive higher resolution image signals of theimaging area than when the imaging unit is disposed further from theoccupants in the vehicle, such as on the steering column or elsewhere inthe vehicle cabin. Furthermore, coupling the imaging unit 108 to thecentral portion 112 allows for a greater field of view when the imagesignals are adjusted based on steering angle or a rate of angularrotation. In addition, by coupling the imaging unit to the rotatableportion of the steering wheel assembly, the field of view of the imagingunit is not further obscured by the rotatable portions of the steeringwheel assembly when the position of the steering wheel assembly relativeto the driver is tilted upwardly or extended.

In addition, in the implementations described above in relation to FIGS.12 through 20, the imaging unit 108 is not visible to the driver orother occupants, which prevents the OMS 100 from distracting orintimidating the driver or other occupants. Furthermore, the modularityof the implementations described above in relation to FIGS. 12 through30 allows the OMS 100 to be integrated more quickly and easily intoexisting and new steering wheel assemblies 104. By disposing the housing303 and other components adjacent the back cover 126 of the steeringwheel assembly 104, it is easier to route the electrical wires from theOMS 100 components and allows the housing 303 to be coupled to anon-deployable surface, as compared to coupling the components closer tothe deployable surface of the driver air bag area. Furthermore, byhaving the OMS 100 disposed on the upper portion of the hub 116 of thesteering wheel assembly 104, the OMS 100 has an unobstructed view of theoccupants of the vehicle even during steering wheel assembly rotation,and the OMS 100 is disposed just below the instrument panel in the fieldof the view of the driver, which may reduce the amount of distraction.

As provided herein, the OMS 100 can be used to monitor a driver or otheroccupant in a vehicle. Using the OMS 100 to monitor the driver or otheroccupant can include providing and/or coupling the OMS 100 to thesteering wheel assembly 104 of the vehicle. The OMS 100 can includeany/all of the OMS 100 components described herein. As outlined above,the OMS 100 can include the imaging unit 108 configured to capture animage signal corresponding to imaging area 110 in the vehicle, where theimaging area 110 encapsulates the driver and/or other vehicle occupant.The imaging unit 108 can be configured to rotate with the centralportion 112 of the steering wheel assembly 104. The steering wheelassembly 104 can be configured to rotate relative to the vehicle'ssteering column 106.

Monitoring the driver and/or occupant can further include capturing animage signal corresponding to the imaging area 110 in the vehicle andprocessing the image signal to identify an analysis region. The analysisregion can be analyzed to determine an occupant information parameter,and the occupant information parameter can, in turn, be analyzed todetermine an occupant state. An output signal can then be provided basedon the determined occupant state. In some implementations, the OMS 100can further include a processing unit 200 to perform one or more of theprocessing, analyzing and outputting steps of the OMS 100. The vehiclecan also include a processing unit 200 separate from the OMS 100 whereone or more of the processing, analyzing and outputting steps of the OMS100 are performed by this (remote) processing unit 200.

While the foregoing description and drawings represent the preferredimplementation of the present invention, it will be understood thatvarious additions, modifications, combinations and/or substitutions maybe made therein without departing from the spirit and scope of thepresent invention as defined in the accompanying claims. In particular,it will be clear to those skilled in the art that the present inventionmay be embodied in other specific forms, structures, arrangements,proportions, and with other elements, materials, and components, withoutdeparting from the spirit or essential characteristics thereof. Oneskilled in the art will appreciate that the invention may be used withmany modifications of structure, arrangement, proportions, materials,and components and otherwise, used in the practice of the invention,which are particularly adapted to specific environments and operativerequirements without departing from the principles of the presentinvention. In addition, features described herein may be used singularlyor in combination with other features. The presently disclosedimplementations are, therefore, to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims and not limited to the foregoingdescription.

It will be appreciated by those skilled in the art that changes could bemade to the implementations described above without departing from thebroad inventive concept thereof. It is understood, therefore, that thisinvention is not limited to the particular implementations disclosed,but it is intended to cover modifications within the spirit and scope ofthe present invention, as defined by the following claims.

What is claimed is:
 1. An occupant monitoring system (OMS) formonitoring at least one occupant in a vehicle, the vehicle having asteering wheel assembly configured to rotate relative to a steeringcolumn, the OMS comprising: a mounting bracket including two mountingtabs that extend from a bottom surface of the mounting bracket forcoupling the mounting bracket to the steering wheel assembly on oppositesides of a central axis of the steering column, the mounting tabs forcoupling the mounting bracket to a rotatable portion of the steeringwheel assembly such that the mounting bracket extends upwardly from thesteering wheel assembly adjacent a central portion thereof, where themounting tabs are spaced apart along the bottom surface of the mountingbracket, the facing surfaces of the mounting tabs and a portion of thebottom surface between the mounting tabs define a U-shaped surface,where the portion of the bottom surface between the mounting tabs isspaced apart from and defines an opening between the steering wheelassembly and the mounting bracket when the mounting tabs are coupled tothe steering wheel assembly such that an electrical connection isextendable through the opening; a housing coupled to the mountingbracket, the housing having a back surface that is disposed adjacent aback cover of the steering wheel assembly; at least one imaging unitcoupled to a front surface of the mounting bracket and disposed withinthe housing, the imaging unit having a field of view inside of thevehicle and being configured to capture an image signal corresponding toan imaging area in the vehicle, the imaging area being within the fieldof view; and at least one lens disposed adjacent the housing and theimaging unit, the lens having a front surface configured for allowinglight to pass therethrough to the imaging unit, the front surface of thelens facing an expected position of at least one occupant in thevehicle, wherein the mounting bracket includes a top surface oppositeand spaced apart the bottom surface, a back surface opposite and spacedapart from the front surface, and side surfaces that extend between thefront and back and top and bottom surfaces, and the housing extendsaround the top and side surfaces of the mounting bracket.
 2. The OMS ofclaim 1, further comprising at least a first light source disposed on aleft side of the imaging unit and at least a second light sourcedisposed on a right side of the imaging unit, and wherein the frontsurface of the lens is further configured for allowing light from thefirst and second light sources to pass therethrough and out of thehousing.
 3. The OMS of claim 2, wherein each of the first and secondlight sources comprises a set of two or more light emitting diodes, eachset of two or more light emitting diodes being disposed on one or moreprinted circuit boards disposed within the housing.
 4. The OMS of claim3, wherein the printed circuit boards are coupled to the mountingbracket, and further comprising a thermal coupling material disposedbetween the printed circuit boards and the mounting bracket, the thermalcoupling material configured for transferring heat from the printedcircuit boards to the mounting bracket, wherein the mounting bracket iscomprises a material for transferring heat from the printed circuitboards to a frame of the steering wheel assembly.
 5. The OMS of claim 4,wherein the thermal coupling material comprises a thermal coupling pad.6. The OMS of claim 4, wherein the thermal coupling material comprises athermal coupling paste.
 7. The OMS of claim 3, wherein at least one ofthe printed circuit boards comprises a processing unit, the processingunit being electrically coupled to the imaging unit and configured forreceiving image signals from the processing unit.
 8. The OMS of claim 7,wherein the processing unit is configured for selecting at least aportion of the image signals as being related to one or more occupantinformation parameters and communicating the selected image signals to asecond processing unit disposed outside of the housing.
 9. The OMS ofclaim 7, wherein the processing unit is configured for selecting atleast a portion of the image signals as being related to one or moreoccupant information parameters, calculating data related to theselected image signals, and communicating the calculated data to asecond processing unit disposed outside of the housing.
 10. The OMS ofclaim 2, wherein the imaging unit is a camera, the camera having a lensdisposed at a distal end thereof through which light enters the camera,and the OMS further comprises a compressible ring disposed between thedistal end of the camera lens and the lens of the OMS, the compressiblering configured for blocking light from the light emitting diodes fromentering the camera lens before the light exits the housing through thelens of the OMS.
 11. The OMS of claim 1, wherein the mounting bracket isseparately formed from a frame of the steering wheel assembly and isfastened to the frame.
 12. The OMS of claim 1, wherein the mountingbracket is integrally formed with a frame of the steering wheelassembly.
 13. The OMS of claim 11, wherein the mounting tabs are coupledto a hub of the steering wheel assembly, the mounting tabs extendingfrom the bottom surface of the mounting bracket beyond a lower edge ofthe housing.
 14. The OMS of claim 1, wherein the lens is configured foroptically blocking visible light and allowing infrared light to passthrough the lens.
 15. The OMS of claim 14, wherein the lens is formedfrom an acrylic-based material that is opaque to visible light.
 16. TheOMS of claim 1, further comprising at least one trim piece shaped to fitaround at least a portion of a side or an upper perimeter of the lens,the trim piece being configured for securing at least a portion of thelens relative to the mounting bracket.
 17. The OMS of claim 16, whereinthe trim piece comprises an upper portion and right and left sideportions that extend from each of the right and left ends, respectively,of the upper portion, the upper portion configured for engaging an upperperimeter of the lens, the right side portion configured for engaging aright side perimeter of the lens, and the left side portion configuredfor engaging a left side perimeter of the lens, wherein the trim piecefurther comprises a first tab and a second tab, the first and secondtabs extending inwardly from the right and left side portions of thetrim, respectively, and each tab defines an opening configured forreceiving a screw, the openings configured for aligning with openingsdefined in the housing and openings defined on the front surface of themounting bracket, and wherein each of the openings in the tabs of thetrim piece, housing, and mounting bracket are configured for receivingthe screw to secure the housing and trim piece to the mounting bracket.18. The OMS of claim 16, further comprising a lens support piece coupledto the mounting bracket adjacent a lower perimeter of the lens, whereinthe lens support piece prevents movement of the lower perimeter of thelens relative to the mounting bracket.
 19. The OMS of claim 18, whereinthe lens support piece defines a channel on an upper surface thereof,and at least a portion of the lower perimeter of the lens is configuredfor engaging the channel.
 20. The OMS of claim 1, further comprising atleast one light source disposed adjacent the imaging unit.
 21. The OMSof claim 20, further comprising a light blocking material disposedbetween the imaging unit and the light source, wherein the lightblocking material extends at least between a distal end of the imagingunit and the OMS lens and is configured for preventing light from thelight source from entering the imaging unit prior to the light exitingthe lens of the OMS.
 22. The OMS of claim 1, wherein the back surface ofthe housing extends within the same plane as the back cover of thesteering wheel assembly, wherein a bottom edge of the back surface ofthe housing defines a shape corresponding to an adjacent portion of anouter surface of the steering wheel assembly.
 23. The OMS of claim 1,wherein housing includes an upper surface that extends transversely tothe back surface, the upper surface including at least one fin toprovide increased surface area on an interior surface of the housing fortransferring heat from the imaging unit to the mounting bracket, the finextending in a direction from a perimeter of the housing to the backsurface.